Two types of parametric four-wave mixing are observed when a single intense laser beam propagates through Na vapor near the D1 and D2 resonance lines. The first is related to three-photon scattering, while the second results from the coherent parametric interaction of the laser with excited-state Raman scattering. Identification of the two processes was greatly facilitated by the use of an optical multichannel detector system to observe the total emission spectrum for each individual laser pulse. The experimental conditions that determine whether stimulated emission or one or both of the four-wave mixing processes dominates the emission spectrum are described.
© 1987 Optical Society of America
Original Manuscript: September 26, 1986
Manuscript Accepted: January 5, 1987
Published: April 1, 1987
Y. Shevy and M. Rosenbluh, "Parametric four-wave mixing processes in sodium vapor," Opt. Lett. 12, 257-259 (1987)